According to the Tech news site AllThingsD reports, Microsoft said on Tuesday that they have identified why part of the Windows Phone 8 restarted, and planned to release OTA updates to fix the fault.

Earlier there were reports that part of the Windows Phone 8 mobile phone users reflected in a number of professional forums that their phone often locked up or rebooted without cause, sometimes up to several times a day. These complaints are mainly related with HTC 8X and Lumia 920.

“We are continuing investigation on the relevant part of Windows Phone 8 phones restart with no reason, and now we have identified the cause of failure with partners,” Microsoft said in a statement. “We are developing the patch which is expected to be released in December.”

However, Microsoft refused to disclose what caused the failure, but also did not say whether the problem is limited to some models, or affect all Windows Phone 8 devices.